Box dumper



IBI

9 Sheets-Sheet l 15o ISI V56 lo E. A! VERRINDER BOX DUMPER us :ma

o O ,0 /z u f-` Sept. 30, i952 Filed May 24. 1951 il j INVE TOR ERNEST A. VERRINDER BY Ww ATTORNEY swept- 30, 1952 l E. A. VERRINDER 2,612,277

BOX" BUMPER Filed May 24. 1951 s; Sheets-sheet 2l V54 Il?, .3 `Z5` I 35 INVENTOR I -l-I 2 l-:R-NEs-'r A. vERRmoER BY MM /QQ-w/ZJ Sept; 30, 1952 E. A. vERRlNDl-:R 2,612,277

Box BUMPER Filed May 24. 1951 9 shew's-slnee'y 5 f y lss INVENTOR engass'r Avennmoen ATTORNEY Sept. 30, 19522 i E. A. VERRINDER 2,612,277

Box DUMPER` Filed May 24, 1951 9 sheets-sheet 4 .--J'l 1E:

INVENTOR ERNEST A. VERRINDER ATTORNEY Sept-30, 1952 i A. VERRlNDER 2,612,277

- l Box BUMPER Filed may 24. 195i l sheets-sheet 5 INVENTOR y ERNEST A. VERRINDER ATToRN EY Sept. 30, 1952 E. A. VERRINDER l 2,612,277

- B'ox BUMPER Filed May 24, 1951 9 Sheets-Sheet 6 INVENTOR ERNEST A.VERRIN DER ATTORNEY Sept. 30, 1952 E. A. vRRlNDER BOX DUMPER 9 Sheets-Sheet 7 Filed- May 24; 1951 l .JY 1 mn A u m m Wn T NE T l? E IiV A im" A. 211A' v. Y 7 1 v.. n R F onuila Sept. 30, 1952 LA.y VERRINDER Box DUMPER 9 Sheets-Sheet 8 Filed May 24, 1951 Rm wm NR n wn m V A. T s E N Y B )00. @N

ATTORNEY Sept- 30, 1952 E. Ag VERRINDER 2,612,277

BOX DUMPER Filed May 24, 1951 9 Sheets-Sheet 9 84| |23 25o t 2%: o 24 226 |55 IGS l i L@ E'IE 1E' 54"n M54 INVENTR ERNEST A. VERRINDER ATTORNEY Patented Sept. 30, 1952 UNITED STATE-s 2,612,217:

Box'DUMPER: ErneSzAaVel'lindiF; Riverside, Calif., assignm; to 'Y F=d1 Machine Mld- Chtmiel- Compiano SM1-Ylos@ Clifls a corporatio1il Qfv BelaWam.: y APP-laiionflYI-arw1951;.seriarisazisiaf (01.,.214-Ldri 11. Gleim;-

This invention relates tofthesartzof.: handling' a loose product in bulkv in opentt'op'. boxes .'andi is;

particularly useful in. dumping.. the contents. from such boxes.

The present application covers. an: improvefl .ment in the box dumpersshown immy.- coependfing applications forl U. S; Letters. Patentf Serial No. 168,789v filedv June 117;` 1950, and; Serial; No. 182,924 filed July 28,1950;I These. prior.'-- applications cover different forms of/aboxfdumperin which a stack of boxes is-elevatedilhtofrictional contact with a horizontallyr travelling'overhead belt conveyor, this contact''causing'the boxesy of the stack to be-successively'froll'ed in the'di'rection of travel of the overheadv conveyor so,y that the contents of each boxl areilclumped` ontov a loose product conveyor and thel empty boxeslare successively propelled# onto an emptybox conveyor.

In the first of said prior applications4 the elevator received thesta'ck atarel'atively sl-ig-l'it'inclination from vertical sothat the'stack could readily rock from anA upright'position-into' alignment with and resting on the elevator 'without too great a shock to the product'- in theboxes; To effect a direct delivery cfj the` product from the boxes onto thek product@ conveyor" at a relatively low level,l they second off-saidy co p f sr1vdir' 1g applications disclosed an elevator s'et 'at/.Vak comparatively steep inclinationA relative to vertical and positioned theboxr dumping conveyor sofas to be engaged bythe uppermostl box?v of` each stack while the staal; is being' fed `to-theelevator whereby this conveyor regulates the speed'wi'th which the stack tilts onto-fthe elevatortoprevent undue shock to the productbythe impaetofthe stack against the elevator;

Inboth of said prior applications,each4 box; as it is being dumped by' thev overhe'ad'conveyoiij'is rolled over a hump-sha-ped fulc'ruin" member 'which terminatesv in a downwardlyinolined de livery board, the latter delivering: thefproduct directly onto the loose productzconveyoit The rolling of the box in vthese"Q-dnmpersils smooth and controlled' as: the boxl doesnt'leave contact with the overhead conveyoruntil, after the dumping is completed; vAs the box, reaches a certain semi-inverted positlomhrlivvey'e"1:,V the loose product therein gravitates fromv thefbox'in a downward surge ontov the Adelivery:.,lcl'iardv and from this ronto the loose product. conveygrf Although this is notf objectionabl in the .uses for which said prior dumpers w .-.levelo ed, certain products require extr'emeere handline to preventiniury thereiny and it aan .obiect a, box.. dumper in` over a. fulcrum.member'ftolbring the leading, edge,

off the lower Aside of, the. boxA relatively! Close." to'. the. loose product. conveyor. so.' that. the product' has only a short distanceto. move. in gaeytat'ng, from the, boxl onto the Vloose prodictl.. conveyor. vAnother.object is toprovide sch'jaboxdlllipit in which the'. major. flow. offthe `produc't. 'fromthe box. 'isI retardedA untill this' close relationship of, the box with the` productv conveyor-ibas been achieved.

The manner. of aoconriplishingV the foregoing objects-as well as further, objectsland advantages will befmade manifest irl-the. following descrip.'-y tion taken in connection with the vaccomp'aiis'ing drawingsin which Fig, 1 isa diagrammatic.sideelevational-v view of a preferred embodiment of thel invention' and illustrates the same receiving a stack of'fo'pen top; boxes loadedv with a loose. product.` as when' the stack has just engaged the overhead'. conlveyor belts. and is beingv lowered under control of said. conveyor towards! a position. of rest. nthe .Stack elevatorf Eisiz. is a front eletaienal viewv0f Eig-e 1 .t2-ken on: the lline 2.1.-..2-. .thereof with @attack-10i .1991925 removed.

Fig. 3 is averticalisectional-view talerronthe line 3-3 of Fig'. 2. A g- Fig. 4. is an. enlarged. plan view; of: the. invention taken.y on. the; line .4g- 4. of; Siinwhich. certain portions of; the structurerarezbroken awaygto; 11eveal. otherwise; hiddemdetails thereof.;

Fig..5. is a fragmentary enlarged crosssectional viewtaken on the line 5-1-5of Fig. 2;.

Fig- 6' isa detailed sectional: view' taken on the line 6--6 of Fig.. 5 and i-llustratinga staclen'd guide of' the invention.

Fig. 7 is a fragmentary operational viewI taken in the samel plane as Fig. S-andI showing the stack...iust.after it has beenldelivered' 'torecline uponrthe inclinedi elevatory and witli'i-ts uppermost: box pressed against the dumping beltszwith said upper boxV thus yrelieving fthexcurtainzsulb.- porting frame. fromcontact. with; saclzbelts. andv permitting said; frame.. to swingto its inwardmost positionrela-tive to .the path alone. which ,Said stack; is being. elevateawith .the-cu I l o impartis@ .by said frame extending' We? me WR@ Sm 'pox' and with the bottom of said box elevated approximately opposite the pivotal axis of the counter-balanced fulcrum member of the invention.

Fig. 8 is a view similar to Fig. 7 and illustrates a succeeding stage in the dumping of the loose product from the uppermost box inthe stack in Which the fulcrum member has rocked about its axis to its lower position, with the box still'res'ting on the initial step section of said fulcrum member, and with the curtain still positioned to retain the product in the box with the box resting approximately upon its side. e

Fig. 9 is a view similar to'Fig. 8k 4and,illustrates a succeeding stage in the dumping of the product 1 from a box wherein the box has been rocked b the dumping belts onto the final step section of the fulcrum member and then further rocked about the leading edge of the lower side of the box whereby the weight of the product in the box 'acts to swing the curtain forwardly and produce a gentle owing'movement of the product downwardly and forwardly from thevbox directly onto the loose product conveyor.

Fig. 10 is a view similar to Fig. 9 and illustrates a'successive step'in thel dumping of the product from ai box'by myjinvention in which the box has Vbeen emptied of product, all of which has been delivered onto the loose product belt,v the box now being delivered onto an empty box convezyorjthe empty box being shown as positioned inthisl view where it has just left contact with the counter-balanced fulcrum member permitting the latter to return to its normal position with the initial step section thereof parallel to and in contact with the adjacent side of the next uppermost box of the rising stack.

Fig. 11 is an enlarged cross-Sectional detail view taken onthe line H-H of Fig. 1 and illustrating the internal structure of the stack elevator.

Fig. 12 is an enlarged fragmentary cross-sectional detailk view taken on the line l2-l2 of Fig.r 3; v

Fig. 13 is an enlarged fragmentary cross-sectionalV detail view taken on the line lili3 of FigfB.

Fig. 14 is a diagrammatic fragmentary perspective view illustrating structural details of the curtain supporting frame ofthe invention.

I Fig. 15 is a fragmentary perspective detail view lReferring specifically to the drawings, the .inu

vention is therein' shown as embodied in a stack conveying andvelevating and box dumping apparatus which is mounted on a pair of vheavy angle members 2i, the latter being getinte and supported bya iioor 22. The apparatus 2li includes a stack conveyor 23, .a stack elevator 2li, a stack controlling and box dumping conveyor 25, a loose product conveyorfZB-K and an empty box lconveyor 2. l ,Y y I 1,

Thestack conveyor 23 includes a pair of lendvlesschains 28 which turn around suitable sprockets=29 which arecarried on stubshafts ,39, the latter being journalled in bearings 3l which are mounted on theangle members 2 I fand on brackets 32 which are supported on the elevator 2d.

fore,v vhorizontal excepting for the extremities thereof immediately adjacent the sprockets Lv29."

This downward inclination of the forward ex= tremities of the tracks 33 towards the pitch lines of the sprockets 29 is for the purpose of causing each stack S of loaded boxes B travelling on the stack conveyor 23 to rock towards the stack ele-- vator 24 as this stack is about to be delivered to said elevatonlthe purpose of this being made clear hereinaiter.'Y`

` The stack conveyor 23H5' driven by power applied to the chains 28 thereof under controls which regulate the delivery of stacks S to the elevator 24 so that each of these stacks is delivered in a timed relation with the operation of said elewhich is not, therefore, described herein in detail.

The elevator Z'has a rigid frame structure llt, including side standards lli (Figs. l, 2, 3 and ll) the latter being secured by bolts t2 to the angle members 2| so as to support the elevator 2e thereon. A plurality of sets of holes 63 are provided in the standar-dse! for the reception of the bolts 42 whereby the angular relation of the standards di with the angle members 2i may be varied by selecting one or the other ofv different sets vof these holes for receiving said bolts when assembling standards dl on the angle members 2 i .Y

The standards lll areV reverse lduplicates of each other so that a description ofone will suffice for both (Figs. 1, 2, 3'and1ll).A Each standard in cludes an outer housing channel 4t and an inner channel 45 which are held together by bolts 46, the channels 45 being rigidly'connected by trans-- verse channels 41, 48 and :i9 which are welded theretoat vertically spaced intervals as shown inFig.` 3. The front flanges of channels 4d are reinforced by stack supporting wear plates 5i) which are removably secured to said channels as by flat headed screws. The brackets 32, aforementioned, are secured to the plates 59 and channels 44 by bolts 5|. Secured as by welding to a forward flange ofthe channel 425 is a vertical angle iron chain'guide 52. Secured as' by bolts 53 to an inner face of each channel allv A'is' an angle chain guide 54. Secured asby bolts 5b to cross channels d8 andV 49 are angle iron members 5S. Secured to the rear flange of channels M by bolts 6U are bearings 6|, these bolts also securing to said channelanglerbrackets 62 having stop lugs 63 and pivotally supported on bolts 3d are counter-balanced chainvsafety latches 65.

Fixed on the outer faces of the angle members at the upper .ends of the standards 4l are cradleguiding cams 6B. rlhese cams arereinforced by Ybrackets 67 which are bolted to cross channel 49. Supported on the cross member il and on suitablev spacers connecting these with the standards I within the lower endsof the latter are cradle cams 68 and', each of the vlatter carrying a trap latch 1! pivotally mounted thereon, this latch, normally resting on a' lug ll provided' onl the adjacent cam 63 (Fig. 3). The mann ner of operation of cams 66, $8 andt will be made clear hereinafter.' Pivotallyfrnounted on upper end walls l2 ofthe standards .4| are trap latches 73 which swing freely about their axes in the planes of the cam 66 and normally rest downwardly on the upper edges of the latten.

Journalled in bearings 'il 'mounted on lower end portions ,of the standards 4i are stub shafts i8 carrying *sprockets 'i9 which rotate in the planes of the jam latches S5 (Fig. '11). Mounted on upper'portions ofl the standards di are two pairs of bearings t0 and 8i inwhichshafts 82 and'SS respectively journal (Fig. 2).* Journalling Vinlbearings 5| is-a shaft 84. The'sh'aft 82 has keyed "thereon sprockets 90, elevator chains 9| 'being-` trainedbabontltheseffandabcutspro'ciietssll Which-lle inJ thel samesverticaflfplanesr therewith:- Fixedlon oneaend offshaft 82- is adrivepsprociiet 92-1- l Fixed L"one corresponding ends" oi-1r shaftsv ,8'3" andQBIivx 'are-l sprockets 93` andi-91V.- Adjustably mounteddon the adjacent outer:- facepfastandard 41I#(Fi 'g--1)` is an idlelsproc-llz'etlfll Trained about thefsprocketssi-JZ, 93 ,l 94 andgiseanendlessfdriye chain 96.

Fixed 'on l`thfeoppositeend offshaft lisalmaster` u sprocket'-v 911 -which is-4 drvenlby: af chain- 98 connectingr this- Jwiti': a; pinionffsprocketf- 9 Sf ofi? a variable; spe'edelctric mctorzpowernnitf-I 00?" The master sprocket 91Tipi'.efi'erabli"fiinzldeswaff-convenel tional v1slipclutch? which aisssetito eslipswii'ene any jam-occurs inrthe-dumper--Nse asetof-minim-ie. the resulting: innryr-tOft-boxesrf beings; handled therein.4

The: shaft"l 831has a opposite end.

Carried` betweenvthelevaron-chains illlare--two equally :spaced` st'acki-rlifting cradles 1059 Each cradle has afsh'aft Ixwiiiclwislrigidlywsecured thereto along one edge .thereotf'andionf opposite ends of.iwhich .rollers -I01ireely-rotateg- Eixedfto thefopposi-te ends A*of -the sh'ait' I 065 are'Ja-rms I 08 which: extend i downwardly atrapproximatelyfaright angle with`l thercradlefI ithe lowenendsfof saidfarms beingl:pivotally secured-*itcf-corresponde ing links .ofsthef-chains-"SI-IKEigsfTand 11) When thefpowen uniti. I U is: energized ttwdrive@the-"elevatoraMgit .'.causesvrotation oftlie shaft82- the direction of"arrowcIIl9?(Fig.- 1')' '=so astolcauseth-e cradlesi I to su'ccessivelyris'esin extended'"relaY tion with the :stack: supporting-wear platese 0 so' as .to: lift Leach' stacktupwardlyfwhile :the boxes f thereof y are s -successivelyf dumpe'dfs Wfhen' eachl cradle I05arrives at the upper endFfof-#th'eeleva'-` tor 24 the rollers IIl'I are-cammed rearwardly by they upper end walls lbfrtherstandardsf# I. This causes these rollers to pass under/:the latches 'I 3 and betrapped behind-the ,cams 6 6 fas .thepivotalconnections of;thatcradl1e III5=-withrthe chainsf IV passK over ,the ,sprockets-SIL i This.- resultsf-in-the withdrawal of th'e.11ppermoshcradle-.l 05 from. itsv extended position. ,and.itsiconnementywithin:the

standards 4 I duringdt's downwardtravel-.fasfshown l Vl11"e n,or1e4 ,of the-I cradles I 05 approaches the: lowerV end of theelevator-Mgthe rollers fI Ill-there of. engage carri. 68 which.,swingsfthissfcradle, forwwardly,gthe latches] -gyielding-toallow sai'durollers to :passfcrwardly' betweenthecarns and-69;,and then dropping :to trap,these rollers ,-inftheiwfore ward Vpositionsand guide themaupwardlxfbetweentheforward, I flangesgof tha channels A:Ihlsarnlf 5'. as shown inEig. 3., t s

Ajframesuperstructure II5 is-mounted omthe upperend'oi the .frame structureill by= meanseoi,y heavy plates II6 which are weldediforotherwise secured ,to upper outer. facesr oztherstandardssei I The. superstructure I I5.includes; af'pairsoff spaced horzontalchannel members vl I1 to-r.whichY trapes:

zoidal platesI I8 are weldedfso/ that saidxplatesa ligagfinstfirmer; facesfofthechannelsgl I'I;Y The. plates. II-aihave l1langefs,;-| I9 and;l20;bentf.f1om op:y positecdges lthereof below-the channeled I] :for: strengthening purposesa-.andfthesemiatesaaref se; cured .tothe plates II-by-.bolts;f1l 2 I .i i Weldedz-ttoi thenamges fl I 9` are-bearingdugsd 2221;, Formed inv portions.;of ..ther-p1atesa I l'zazdisposed betweenithel interned .-flangesaoffthe channels-I I'If; arexarcuate camslots I23.f,y i

Theaovierhead eboxnqidumpingsconvcyorz S'fine pairs ofarmsfllhand-L'IBQE- Each of. blocks I these springs being secured bylbracketsS-I "I3-td the zontal axis onsaid. channels: 'The' 'right endV 'of section |85 is 'yieldablyl'z supported on rods. I 8'6? which connect p-ivotally therewithandextendtup therefrom through suitable holes' forinedinupier flanges of channelsI'I I'I' 'andthrouglimoiled l'ex-f pansion springsIfI',` to receive"washers^l8U'and nuts weinige). l v

' The lo'oseproduct conveyor'l26 (Fig: 3)` is loi cated just below the empty box conveyor 21"'an'd the: right -hand fi or receiving u'eIidftliereof jisrloe" of elevator 24, and approximately on the same level' as the latter. Conveyor26 is showndiagrammatically as l ap' ower driven belt but may elevatorv 24 llifts stacks o fj boxes,v and the receive ing @milr of product conveyor 26ers a fulcrum member 2004 an d a loosegproduct control mech'.v ansm 2|)lllr'fss,i5. -14 and 15).-, 1

Ther fulcrummernberj 200'comprises an initial step section 205 and-a nalstep section 206 which arejoinedtogetherat `their meeting edges by a continuous y-hinge 261 (Fig.V 15). The in itial step section, 2D5has ja wide notch 208 cut from itsjlower edgeto accommodate vpassage of stack cradles v|05 fromextended to retracted position as shown in Fig. 3, and .is provided with a pair of collars 209 adjacent this lower edge (Fig. 13). Fixed virl-these collars are a short shaft 42 I0 and a shaft 2I| (Fig. 13), these-shafts journalling in suitable aligned holes formed in plates 8, the outer end of the shaft 2| being bent to form an arm 2|2 which extends to the right and adjustably carries a counter-balance weight 2|3 (Fig. 1). This'fweight constantly rotates the fulcrum member 200 to bring the initial step section 205 thereof into contact with a pair of rubber cushions 2 Ill (Fig. 5) which are mounted boxes 2|5welded Vtotheinner faces of the plates 262. A stiflening bar 2I6- s secured to the bottom face of initial stepsection 205 closeto the upper edgethereof.

The nal step section 206 is preferably formed of. a sheetv o f metal bent against itself at the leading edge 220'of said member (Fig 15) so as toprovide an apron 22|, there being a slight space between said section and said apron into which slightly `bent leaf springs 222 extend, op posite -ends'of these springs being V.secured by clamps 223 to the initial step section 205.l Suitable gaps are provided in the hinge 201 through which springs 222 extend. The apron 22| is secured as by rivets 224 tothe final step section 266so that thedegree of flexing between the sections 205 and 206 is ygoverned by the springs 222 which are relatively sti and the functionr of which' will be made clear hereinafter in describing the operation of the invention. The entire .upper face of the fulcrum -member 200 is preferably, covered with a resilient plastic coating 200'a'approximately 1A; inch thick. v The product control mechanism includes a shaft 225 opposite ends of which journal l'in bearing lugs |22. The leading edge of asheet metal back board 226 is mounted onthe Vshaft 225 opposite end edges of said back boardbeing bent downwardly and welded to collars 221. The mechanism 20| also includes a rectangular frame 230having side members 23| which are connected at their upper and lower Vends by arcuate oross'members 232 and 233, which are Welded to Yinner faces of said side members 22|. Also so welded,` just inwardly from said cross members 232"`and 233', are collars 234 and 235 the holes of said collars continuing through said side members. Shaft 236 is supported in the collars` 23'4 and fixed therein by suitable Vset screws.; Suspended rotatably on shaft 236 is a curtain231 which may be formed of heavy beltprovided along its ing, sheetrubber or` the like, this curtain beingV supported onvshaft 2.36 byva series of clips 238 upper edge. Extending through .the collars 235 and fixed therein by suitableset screws is a shaft 240 this shaft also extending through the collars 221 of the back board 226 (Figs. 5 and 14) so asto pivotally connect the VmembersZ-)l with the back board 226.

Members 23| are provided with short rearwardextensions, 24 Y Fig.,11)v carrying pins 2 42 Y which extendroutwardly therefrom through the arcuatecam slots .|23 and carry flanged rollers 243 which space the-members123| from thefplates Il and extend into :the slots |23l so as to support the frame 236v on saidrollers. 'Ihe action of curtain frame236 Aand'baclr board 226 is thus determined by the shape of cam slots I 23.. Disposed between the plates H8 and the channel members ||1 and connected to the pins 242/are contractile coil .springs 250 the opposite ends of which connectwith suitable'brackets 25| f which aresecuredto inner faces of the channel menibers ||1(Figs. 7 andf14).

Clamped in place against inner faces of-plates H8 adjacentthe inner ends of the arcuate cam slots |23 by clamps 252 (Fig. 5) are rubber blocks 253 whichserve as cushionstops for the frame 236 when this isfreeto be drawn by the springs 25|linto its extreme rightward position.

Secured tothe flanges-|20 by'bolts 260 (Figs. 5 and 13) and to the upper flanges of members 1 by bolts 26| aretriangular sheet metal guards 262 which are shapedto-guide the upper box of astack intocentered relation with the machine and prevent thegends of. thebox catching on stops 2M and 253 or on side members 23| of the frame 236.1. v

' v OperationV As before `noted the y ele'n/ator 24 is set in op'- eration74V by venergizing the power unit |60 which alsov drives the overhead belt conveyor 25through thevr chain |35.-r Withfthejdumper 20 thus running and with power Yapplied to the product conveyor 26 so as to' cause thevupper ightther'eof to travel in thedirection ofthe arrow adjacent thereto, a stack of boxes S is caused to be fed along the floor track conveyor 23 so that this tilts -to bring the upper Vend of the stack into engagement with the lower fiightsf|1| of the overhead belts |10 as shoWn'lFg. 1.'V The uniform,`relatively slow rate*a t"which" the belts |10 travel,fand the pressure with which these belts are held-taut bythe springs |12 and |11, causes the downward tilting 0f this stack to be controlledftofprevent an acceleration of the tilting of this stack by gravity which would produce such-a shockfupon its stopping'against the elevatorlias would be'injurio'us to the product carried in the'b'oxes. f

kIt is j to be noted 'that the idle pulleys |66 and |15 are vpulleddownwardly against the lower flights |11 ofbe'lts'l'lll by the springs |12 and |11 so -that,'as the -pulleys |66 are swung upwardly outffrom'in front of the path `of the uppermost box. of the stack entering thedumpenrollers |15 automatically swingdownwardly into the path of the stack so asto maintain belts |10 frictionally engaging the leading corner of the uppermost box so. as to positively prevent escape of the stack fromwcontrol by the belts and thereby cause the entire downwardv swinging of the stack to'be held to a rate determined by the speed of travel of the conveyor 25.y Thisy results in the stack beingl deposited gentlyv ina position of rest against member and empty box receiving conveyor so that said belt is engaged by the uppermost portion of the uppermost box of said rising stack; and means for moving said belt lengthwise across said path to frictionally engage and roll said box against and over said fulcruml whereby the latter is caused to yieldingly rock about its axis to gently lower said box to bring the leading edge of the lower side of said box close to said product conveyor and tilt said box while so positioned towards said conveyor causing the product to ow from said box onto said product conveyor, themovement of said belt continuing to shift said box to deliver the `latter when empty onto said empty box conveyor;

2. A combination as in claim l in whicha yieldable curtain mount is provided; a curtain carried by said mount; means biasing said mount towards said path so as to shift said curtain over the top of the uppermost box of a stack when the latter rises into engagement with said belt said means yielding with the movement of said box, as the latter is rolled by said belt as aforesaid, to

- maintain said curtain in covering relation with the open top of said box as said box rocks downwardly into product dumping relation with said product conveyor, said curtain being free to then yield to pressure of said product to permit the latter to gravitate from said box onto said product conveyor.

3. In a stack dumper the combination of; an elevator adapted to receive and elevate a stack of loaded open top boxes' along a given path; a fulcr-um'member at oneside of said path; a loose product conveyor on the opposite side of said fulcrum member from said path for receiving product from a box; an empty box conveyor above said product conveyor for receiving empty boxes; a curtain; a curtain mount carrying said -curtain and biased toward a position in which said curtain overlies the open top of an uppermost box of a stack in said dumper; 'a flexible belt; means for suspending said belt in a stretched condition and extending through said Vpath and over said fulcrum member so as to be engaged by the uppermost portion of the uppermost box of said rising stack; and meansfor moving said belt lengthwise across said path to frictionally roll said box against andover said fulcrum member, said curtain mount being engaged by and yielding before said box, as it is rolled by said belt, to retain said curtain in covering relation with the open top of said box until the leading edge of the lower side of said box is relatively close to said loose product conveyor, whereupon said curtain yields before the weight of the product in said box to permit said product to' gravitate past said curtain and onto said product conveyor, and said box, thus emptied, is propelled by said belt over said curtain and onto said empty box conveyor.

4. In a stack dumper the combination of: an elevator adapted to receive and elevate a stack of loaded open top boxes along a given path; a fulcrum member eccentrically pivoted along its lower edge on'a horizontal axis close to said path and close to the bottom ofthe uppermost box of said stack when said box arrives in. position to be dumped; means to bias said fulcrum member upwardly into parallelism with said box'and close to one'side thereof, but permitting said fulcrum member toyield resistingly away from said path; a loose product conveyor on the opposite side of said fulcrum member from said path for receiving the contents of a box; an empty box conveyor 12 above said loose product conveyor to receive an empty box; and a box rolling mechanism for engaging said box when in a position to be dumped as aforesaid and shifting the latter against said fulcrum member to rock the box and said member about said axis Awhereby the leading edge of thebottom side of said box is lowered into proximity with said loose product conveyor and the product in the box caused'tc gravitate onto said conveyor, said box propelling means continuing to engage and propel said box whereby said box is shifted onto said empty box conveyor, said fulcrum member returning to its original position when dis-engaged by said box.

5. In a' box dumperthe combination of: means for delivering a loaded open top box into a noninverted position; a fulcrum member mounted pivotally on a horizontal axis disposed close to one side of said box; means for applying a rotative bias to said member resisting rotation thereof awayfrom said boxfand returning said'mernber Yto its original position when it is released; a loose product conveyor on the opposite side of said fulcrum member from said box; an empty box con= veyor disposed above said product conveyor; and means for propelling said box against said fulcrum member to rock the latter about its axis towards said'product conveyor with said box resting on said fulcrum member until the leading edge of the lower side of said box approaches close to said productwconveyo'r and vsaid box assumes a semi-inverted'positioncausing product therein to gravitate therefrom onto said product conveyor said box propelling means continuing to operate on said box to propel the latter, when emptied, onto said empty `box conveyor.

r6. A combination as in claim 5 including a curtain; means forA movably mounting said curtain said means biasing said curtain towards a position above saidbox, when the latter is initially propelled against said fulcrum member, so as to cover a portion of the Vopen top of said box,

assaid box moves into the aforesaid semi-inverted position, to retain the product in said box Vagainst premature gravitation therefrom un til said leading edge of said lower side of said box approaches close to said product conveyor said curtain then yielding to the weight of said product to permit the latter to be discharged onto said product conveyor, said curtain mount yielding downwardly to permit said box propelling means to continue propelling said box after it is emptied, onto said empty box conveyor.

`'7. A combination as in` claim 6 including a .back board located along the receiving end of said' product conveyor; and means for elevating said back board to prevent product backing off the receiving end of said conveyor as said box is fully inverted at the conclusion of the dumping operation and shift'edaway from over said fulcrum member whereby the llatter is'restored to its initial position.

8. A combinationl as in claim 7 in which said b'ox propelling means comprises an overhead endlessV belt conveyorwhich is positioned to frictionally engage eachbox delivered intodumping position and rotate said box in propelling the same as aforesaidfrom its initial position towards its inverted'empty position on said empty box conveyor; and means yieldably supporting 'the receivingend of said empty box conveyor whereby the latter yields downwardly to accommodatethe empty box between said empty box conveyor and said overhead box propelling conveyor. Y l

9. In a box dumper the combination of: means for delivering a loaded open top box into a noninverted position; a fulcrum member disposed close to one side of said box when so positioned and close to the bottom of said position; a loose product receiving conveyor on the opposite side of said fulcrum member from said box; a curtain adapted to cover a portion of the open top of said box during the dumping operation; a shiftable mount for said curtain which biases said curtain towards a position in which said curtain is above said box and covering a portion of the open top thereof in the initial phase oi the box dumping operation; and means to engage said box and roll the same towards and over said fulcrum member to bring the leading edge of the lower side of said box close to said product conveyor with the box in semi-inverted position, said mount yielding with said curtain to pressure of said box thereagainst as said box is so rotated whereby said curtain covers a portion of the open top of said box to retain the product within said box until the latter reaches its semi-inverted position aforesaid whereupon said product gravitates against said curtain, swings this aside and is discharged onto said product conveyor, said box propelling means continuing to propel said box towards said empty box con veyor whereby said box is delivered over said curtain onto said empty box conveyor.

10. A combination as in claim 9 in which said vcurtain mount includes side arms located beyond of said loose product conveyor said back boardv being connected to said side arms of said curtain mount whereby said back board is elevated as said curtain is depressed by a box, just inverted and emptied of product, whereby said product is retained by said back board on said loose product conveyor.

ERNEST A. VERRINDER.

No references cited. 

